{"id":16617,"date":"2022-03-25T22:34:02","date_gmt":"2022-03-26T05:34:02","guid":{"rendered":"https:\/\/essential.construction\/academy\/?p=16617"},"modified":"2026-11-04T07:13:52","modified_gmt":"2026-11-04T14:13:52","slug":"elevator-pit-waterproofing-with-crystalline-technology","status":"publish","type":"post","link":"https:\/\/essential.construction\/academy\/tutorials\/elevator-pit-waterproofing-with-crystalline-technology\/","title":{"rendered":"Elevator Pit Waterproofing with Crystalline Technology"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong>Elevator pit waterproofing<\/strong> keeps groundwater out of the concrete box at the bottom of the elevator shaft. Because the pit is usually the lowest point in the building, and often sits below the water table, every slab, wall, joint and penetration has to resist hydrostatic pressure. It is also a code issue: the ASME A17.1\/CSA B44 elevator code requires permanent provisions to prevent groundwater from accumulating in the pit. This guide compares the main methods and explains how crystalline waterproofing is used in new and existing pits.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It is written for project managers, site supervisors and designers who need a pit that stays dry, from detailing a new pit to repairing one that already leaks.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What an Elevator Pit Is and Why Water Is a Problem<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The elevator pit is the part of the hoistway below the sill of the lowest landing door, down to the pit floor. In most buildings it is a cast-in-place concrete slab with four walls of concrete or concrete block. It may include a sump, and a hydraulic elevator with an in-ground jack will also have a cylinder casing passing down through the slab.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Elevators have changed enormously since the first passenger safety elevator, from Elisha Otis&#8217;s company, entered service in New York&#8217;s E. V. Haughwout Building in 1857: Taipei 101&#8217;s cars travel at about 37 mph, Jeddah Tower (designed to exceed 1,000 m, or 3,281 ft) has been specified with double-deck cars rising about 660 m (2,165 ft), and Otis alone reports moving more than 2 billion people a day. Every one of those systems still ends in the same simple concrete box.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Water in that box causes trouble out of proportion to its size. Buffers, switches, wiring and hydraulic jacks are not built to sit in water, so a flooded pit usually shuts the elevator down until it is pumped out and inspected. Groundwater also carries chlorides and sulfates into the concrete&#8217;s pores and cracks, corroding reinforcement over time.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Why Elevator Pits Leak<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">When a pit leaks, the water nearly always comes through one of these routes:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Hydrostatic pressure.<\/strong> The pit is the deepest part of the foundation, so a high or seasonal water table pushes against every joint and defect, sometimes from several feet of head.<\/li>\n\n\n\n<li><strong>Cold joints.<\/strong> The joint between the base slab and the walls, plus any horizontal lifts in the walls, are the classic leak paths.<\/li>\n\n\n\n<li><strong>Tie holes and honeycombing.<\/strong> Pits are small, congested and hard to vibrate properly, so voids and poorly sealed form ties are common.<\/li>\n\n\n\n<li><strong>Cracks.<\/strong> Drying shrinkage, restraint and settlement all crack the slab and walls.<\/li>\n\n\n\n<li><strong>Penetrations.<\/strong> The hydraulic cylinder casing, sump, drains, conduits and anchors for rails, buffers and ladders all break the concrete.<\/li>\n\n\n\n<li><strong>Barrier failures.<\/strong> On membrane systems, laps, terminations and corners fail, or the sheet is punctured during backfill.<\/li>\n\n\n\n<li><strong>Water from above.<\/strong> Not all pit water is groundwater: a flooded lobby, sprinkler discharge or a burst pipe can send water down the hoistway.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Code Requirements for Elevator Pits<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In North America the elevator code is ASME A17.1\/CSA B44, adopted with local amendments. The 2016 edition, for example, includes these pit requirements:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The pit must have permanent provisions that stop groundwater collecting in it (2.2.2.3).<\/li>\n\n\n\n<li>Any drain or sump pump must comply with the applicable plumbing code and include a positive means of keeping water, gases and odors out of the hoistway (2.2.2.4).<\/li>\n\n\n\n<li>For elevators with Firefighters&#8217; Emergency Operation, a drain or sump pump must be able to remove at least 3,000 gal\/h (11.4 m\u00b3\/h) per elevator (2.2.2.5).<\/li>\n\n\n\n<li>Sumps and sump pumps in the pit must be covered, with the cover secured and flush with the pit floor (2.2.2.6).<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Local plumbing and elevator authorities decide where pit discharge may go (sanitary, storm or an indirect connection) and whether hydraulic elevators need an oil separator, so confirm the adopted code edition and amendments early in design.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The code does not say how to keep groundwater out, and a sump only removes water that has already got in; it is no substitute for waterproofing.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Elevator Pit Waterproofing Options<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">There are three broad ways to keep water out of a pit, defined by where the protection sits relative to the water.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Positive-side (exterior) waterproofing<\/strong> goes on the face of the concrete that meets the soil: sheet or fluid-applied membranes or bentonite on the outside of the walls and under the slab. It puts the barrier where the water is, but installers need open excavation around the pit and enough room to work. The weak points are the fine details, such as laps, termination bars, inside and outside corners and the transition to the main foundation waterproofing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Blindside (pre-applied) waterproofing<\/strong> is used when the pit is built tight against <a href=\"https:\/\/essential.construction\/academy\/glossary\/shoring\/\">shoring<\/a>, soil nails or an adjacent structure and there is no room to work outside it. The membrane is fixed to the shoring and the concrete is cast against it. This describes an installation method rather than a material. Because the membrane is buried the moment the concrete goes in, it cannot be inspected or repaired afterwards, so every seam and corner has to be right first time.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Integral and negative-side waterproofing<\/strong> makes the concrete itself the barrier, or treats it from the inside. Crystalline admixtures are added to the concrete at the batch plant, while crystalline coatings and cementitious treatments can be applied to either face of hardened concrete, including the inside of an existing pit.<\/p>\n\n\n\n<figure class=\"wp-block-image alignfull size-large\"><picture><source srcset=\"https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited.webp 2560w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-300x169.webp 300w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-1024x576.webp 1024w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-768x432.webp 768w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-1536x865.webp 1536w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-2048x1153.webp 2048w\" sizes=\"auto, (max-width: 2560px) 100vw, 2560px\" type=\"image\/webp\"><img loading=\"lazy\" decoding=\"async\" width=\"2560\" height=\"1441\" src=\"https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited.jpeg\" alt=\"-\" class=\"wp-image-16623 sp-no-webp\" srcset=\"https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited.jpeg 2560w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-300x169.jpeg 300w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-1024x576.jpeg 1024w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-768x432.jpeg 768w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-1536x865.jpeg 1536w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/264A6577-DE52-449B-8E7E-3ABF28D17A85-edited-2048x1153.jpeg 2048w\" sizes=\"auto, (max-width: 2560px) 100vw, 2560px\"><\/picture><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Comparing Elevator Pit Waterproofing Methods<\/h3>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>System<\/th><th>Where it goes<\/th><th>Advantages<\/th><th>Risks and limits<\/th><\/tr><\/thead><tbody><tr><td>Sheet membrane<\/td><td>Outer face of walls and below the slab<\/td><td>Long track record; thickness controlled at the factory<\/td><td>Needs room to excavate; laps, corners and terminations can fail; must be protected from backfill damage<\/td><\/tr><tr><td>Bentonite sheets or panels<\/td><td>Below the slab and outside the walls, including blindside<\/td><td>Swells and self-seals when wet; can be fixed to shoring<\/td><td>Must be confined; groundwater chemistry matters; can activate too early if wetted before concrete is placed<\/td><\/tr><tr><td>Fluid-applied membrane<\/td><td>Outer face of walls<\/td><td>No seams; follows awkward shapes<\/td><td>Film thickness relies on the applicator; needs a dry, clean surface<\/td><\/tr><tr><td>Blindside membrane<\/td><td>Fixed to shoring or lagging before the pour<\/td><td>Works with zero working space outside the wall<\/td><td>Hidden once cast; seams cannot be checked or repaired later<\/td><\/tr><tr><td>Crystalline admixture<\/td><td>Mixed into the concrete at the batch plant<\/td><td>Whole section treated; no laps or separate crew; can seal fine static cracks<\/td><td>Joints, penetrations and moving or wide cracks still need detailing; relies on well-placed concrete<\/td><\/tr><tr><td>Crystalline coating<\/td><td>Inside or outside face of hardened concrete<\/td><td>Can be applied from inside an existing pit<\/td><td>Surface preparation and curing are critical; will not bridge moving cracks<\/td><\/tr><tr><td>Injection grout<\/td><td>Pumped into active cracks and joints<\/td><td>Quickest way to stop running water<\/td><td>Seals only the treated crack or joint, not the surrounding concrete<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For most new pits the sensible answer is layered protection: one primary system for the concrete (a crystalline admixture or a membrane), waterstops plus a secondary treatment at every joint, and a properly sealed detail at each penetration.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How Crystalline Waterproofing Works<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Crystalline products are cement-based powders containing Portland cement, fine sand and a proprietary blend of reactive chemicals. As concrete hydrates it leaves soluble by-products in its pores. When the crystalline chemicals and those by-products meet in the presence of water, they react to form insoluble, needle-like crystals that grow into the capillary pores and hairline cracks. The concrete&#8217;s permeability falls, and if water later enters through a new fine crack, the reaction can restart and seal it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The same chemistry is sold in three forms: an admixture dosed into the mix, a slurry coating brushed or sprayed onto hardened concrete, and a dry-shake broadcast onto fresh slabs. In ACI 212.3R terms, crystalline admixtures are usually classed as permeability-reducing admixtures for hydrostatic conditions (PRAH), which is the category to ask for below the water table, as opposed to products meant only for damp-proofing (PRAN).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Be careful with performance claims. Manufacturers publish permeability tests under methods such as U.S. Army Corps of Engineers CRD-C48 and EN 12390-8, along with figures for crack sealing, chemical resistance and strength. Data sheets for standard admixture grades typically claim self-sealing of static hairline cracks up to about 0.4 mm. Ask for independent test reports on the exact product, check that the test conditions resemble your site, and remember that no admixture seals moving cracks or badly made joints.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Where crystalline systems fit and where they do not<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Crystalline systems suit pits with poor exterior access, because the concrete carries the protection and there are no laps to fail or membranes to protect during backfill. The same product family also works from the inside for repairs. Their limits are just as clear: they depend on sound, well-consolidated concrete, and they do not bridge joints or cracks that move, which still need waterstops or a flexible system.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Designing a New Pit With Crystalline Waterproofing<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Using an integral crystalline system does not change the structural design. The pit is still a structural base slab with walls cast on top of it, and the slab-to-wall joint is protected with a waterstop and crystalline treatment.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Admixture or coating?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The choice depends on site access, programme and the thickness of the concrete. Manufacturer guidance generally finds the admixture cheaper for elements up to about 18 in (450 mm) thick, with a surface coating becoming more economical in thicker sections once preparation, application and curing labour are counted. Price both on a cost-per-square-foot basis for your pit.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Using the admixture<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Take the dosage from the product data sheet. Standard grades are commonly about 2 to 3 percent by weight of cementitious material, but concentrated grades use less and some coloured grades more, and slag or Class C fly ash in the mix affects the calculation. With Class F fly ash, the dose is usually based on the Portland cement and slag content only.<\/li>\n\n\n\n<li>Add the admixture at the batch plant and mix it thoroughly before the truck leaves; the manufacturer&#8217;s instructions typically call for at least five minutes of mixing.<\/li>\n\n\n\n<li>After that, pumping, placing, vibrating and finishing are the same as for ordinary concrete. Good consolidation in congested corners matters more than the admixture.<\/li>\n\n\n\n<li>Note the admixture on the mix design submittal and on delivery tickets, so the inspector can confirm every load for the pit was treated.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Using a crystalline coating<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Where the design calls for a coating, it is applied to the pit walls and floor after the forms come off. Manufacturer instructions typically include:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Clean and open the surface pores, commonly with a high-pressure water blast in the 3,000 to 4,000 psi range, or by light abrasive blasting.<\/li>\n\n\n\n<li>Bring the concrete to a saturated surface-dry condition, wet but with no standing water.<\/li>\n\n\n\n<li>Apply the slurry by brush or spray at the specified coverage, usually in two coats on below-grade work.<\/li>\n\n\n\n<li>Keep the coating damp while it cures, typically misting it two to three times a day for two days, or use the curing product the manufacturer approves.<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-image alignfull size-large\"><picture><source srcset=\"https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200-1024x576.webp 1024w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200-300x169.webp 300w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200-768x432.webp 768w,https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200.webp 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" type=\"image\/webp\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200-1024x576.jpeg\" alt=\"-\" class=\"wp-image-16620 sp-no-webp\" srcset=\"https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200-1024x576.jpeg 1024w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200-300x169.jpeg 300w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200-768x432.jpeg 768w, https:\/\/essential.construction\/academy\/wp-content\/uploads\/sites\/22\/2022\/03\/05EC67DF-5DCF-4F8F-BBC4-26479F830200.jpeg 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\"><\/picture><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Detailing the Slab-to-Wall Joint<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Joints are where most pits fail, whatever system protects the concrete in between. Plan on two lines of defence at every construction joint:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Primary:<\/strong> a waterstop, either a PVC waterstop cast across the joint or a swelling (hydrophilic rubber or bentonite) strip placed on the slab before the wall is poured.<\/li>\n\n\n\n<li><strong>Secondary:<\/strong> crystalline treatment of the joint itself, as described below.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A typical sequence, based on published manufacturer details, is:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Fix a timber reglet strip to the wall formwork along the line of the joint so it casts a groove about 1 in (25 mm) high and 1-1\/2 in (37 mm) deep at the base of the wall.<\/li>\n\n\n\n<li>Install the waterstop, and brush a slurry coat of crystalline material onto the slab where the wall will sit, 24 to 48 hours before the wall pour.<\/li>\n\n\n\n<li>After the wall is cast and stripped, remove the reglet strip.<\/li>\n\n\n\n<li>Mix crystalline powder with water to a stiff dry-pack consistency (about 6 parts powder to 1 part water by volume) and ram it into the groove in layers with a packer or a block and hammer until it is full.<\/li>\n\n\n\n<li>Finish with a coat of crystalline slurry over a band about 6 in (150 mm) up the wall and 6 in out across the slab.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">The extra cost of doing both is small compared with breaking out and repairing a leaking joint after the elevator is installed.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Elevator Pit Waterproofing Details Checklist<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Slab-to-wall joint: waterstop plus crystalline slurry and dry-packed reglet groove<\/li>\n\n\n\n<li>Wall corners and any vertical or horizontal wall joints treated the same way<\/li>\n\n\n\n<li>Form ties: waterproof tie systems, or ties cut back and holes patched and treated<\/li>\n\n\n\n<li>Sump: cast monolithically with the slab if possible, or its joints detailed like any other construction joint<\/li>\n\n\n\n<li>Hydraulic cylinder casing: sleeved, with a waterstop collar or a seal rated for the hydrostatic head<\/li>\n\n\n\n<li>Rail bracket, buffer and ladder anchors: locations fixed before waterproofing, and any later holes sealed<\/li>\n\n\n\n<li>Pit waterproofing tied continuously into the main foundation waterproofing, with no gaps at the pit edge<\/li>\n\n\n\n<li>Pre-pour check of reinforcement cover and access for vibrators in congested corners<\/li>\n\n\n\n<li>Mix design, delivery tickets and admixture dosage recorded for every pit pour<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Use the <a href=\"https:\/\/essential.construction\/files\/design\/autocad\/elevator-pit-detail\/\">elevator pit detail drawing<\/a> as a starting point for coordination and a <a href=\"https:\/\/essential.construction\/files\/construction\/quality\/concrete-pre-pour-checklist-verticals\/\">concrete pre-pour checklist for vertical elements<\/a> to catch missing waterstops before the walls are cast.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Repairing an Existing Leaking Elevator Pit<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Once a pit is backfilled and the elevator is installed, the outside is out of reach. Repairs are therefore made from inside the pit (the negative side), using crystalline repair materials alone or together with water-reactive injection grouts, which are compatible.<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Make the pit safe.<\/strong> Have the elevator contractor take the car out of service and protect the pit equipment before any work starts.<\/li>\n\n\n\n<li><strong>Map the leaks.<\/strong> Mark every joint, crack, tie hole and defect that is wet or stained, and note which are actively running.<\/li>\n\n\n\n<li><strong>Cut out the leak paths.<\/strong> Chase a groove along each leaking joint and crack, and open up a cavity at point leaks such as tie holes and honeycombed patches.<\/li>\n\n\n\n<li><strong>Stop running water.<\/strong> Plug active flows with a fast-setting hydraulic cement, pressing it into the cavity and holding it until it sets.<\/li>\n\n\n\n<li><strong>Fill the grooves.<\/strong> Pack the rest of each groove and cavity with crystalline material in dry-pack consistency.<\/li>\n\n\n\n<li><strong>Inject where needed.<\/strong> For wide cracks, cracks that move, or flows that will not stop, inject a water-reactive grout.<\/li>\n\n\n\n<li><strong>Coat the pit.<\/strong> Once the leaks are stopped, apply a crystalline coating, typically two coats, to the whole pit surface. This deals with seepage through pores and micro-cracks too small to chase out.<\/li>\n\n\n\n<li><strong>Cure, monitor and record.<\/strong> Cure as directed, recheck the pit after heavy rain and log the repair in the maintenance file. Take groove sizes, mix ratios and coverage rates from the repair system&#8217;s published details.<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">What to Do If an Elevator Pit Floods<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Shut the elevator down and call the elevator contractor; never run the car down into a flooded pit.<\/li>\n\n\n\n<li>If the water is coming from a plumbing or sprinkler leak, isolate it, then pump the pit dry.<\/li>\n\n\n\n<li>Work out where the water came in: groundwater through joints, cracks or penetrations, or surface water down the hoistway.<\/li>\n\n\n\n<li>Before the elevator goes back into service, have the elevator mechanic check buffers, switches, wiring and, on hydraulic units, the jack and casing.<\/li>\n\n\n\n<li>Fix the leak path from the inside (see Repairing an Existing Leaking Elevator Pit above) and keep a record of the repair.<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">Key Takeaways<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A dry pit comes from the details, not from one product: establish the groundwater level early, pick a primary system that suits site access and section thickness, give every joint a waterstop plus a secondary treatment, seal each penetration and check the concrete before it is poured. Where outside access is limited or an existing pit already leaks, crystalline systems let you waterproof the concrete itself from either side.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Frequently Asked Questions<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Do elevator pits need to be waterproof?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Yes. ASME A17.1\/CSA B44 requires permanent measures that stop groundwater collecting in the pit, and even small amounts of water can damage pit equipment and take the elevator out of service.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Does an elevator pit need a sump pump?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Not in every case. ASME A17.1-2016 requires a drain or a sump pump able to remove at least 3,000 gal\/h (11.4 m\u00b3\/h) per elevator where the elevator has Firefighters&#8217; Emergency Operation. Any drain or sump that is installed must meet the plumbing code and be covered, and local rules may go further.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Can you waterproof an elevator pit from the inside?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Yes. Existing pits are normally repaired from the inside, or negative side, because exterior membranes cannot be added once the pit is backfilled. The usual toolkit is hydraulic cement for running leaks, crystalline dry-pack and coatings, and injection grout for wide or moving cracks.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How do you fix a leaking elevator pit?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Take the elevator out of service, map the leaks, chase out the leaking joints and cracks, plug running water with hydraulic cement and fill the chases with crystalline dry-pack. Inject grout into wide or moving cracks, then coat the whole pit with a crystalline coating and cure it as directed.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What is crystalline waterproofing?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Crystalline waterproofing is a cement-based treatment whose reactive chemicals combine with water and the by-products of cement hydration to grow insoluble crystals inside the concrete&#8217;s pores and hairline cracks, making the concrete itself resist water. It is supplied as a concrete admixture, a surface coating or a dry-shake.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How much does elevator pit waterproofing cost?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">There is no standard price; it depends on pit size and depth, how far below the water table it sits, site access and the system chosen. In new construction an integral admixture often costs less than a membrane because there is no separate crew or protection board, while repairs to an existing pit are priced on the number of leaking joints, cracks and penetrations to treat.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Related Templates and Guides<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/essential.construction\/files\/design\/autocad\/elevator-pit-detail\/\">Elevator Pit Detail (AutoCAD)<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/essential.construction\/files\/construction\/quality\/quality-checklist-waterproofing\/\">Quality Checklist \u2013 Waterproofing<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/essential.construction\/files\/construction\/quality\/construction-operations-forms-request-for-waterproofing\/\">Request for Waterproofing Inspection<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/essential.construction\/files\/construction\/quality\/water-leak-test-checklist\/\">Water Leak Test Checklist<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/essential.construction\/files\/construction\/quality\/concrete-pre-pour-checklist-verticals\/\">Concrete Pre-Pour Checklist (Verticals)<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/essential.construction\/academy\/tutorials\/building-foundations\/\">Building Foundations 101<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/essential.construction\/academy\/tutorials\/a-best-guide-to-formwork\/\">Concrete Formwork in Construction<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/essential.construction\/academy\/tutorials\/video-roundup-elevators-escalators\/\">Video Roundup \u2013 Elevators and Escalators<\/a><\/li>\n<\/ul>\n\n","protected":false},"excerpt":{"rendered":"<p>Understand what crystalline Waterproofing is and it\u2019s application in construction.<\/p>\n","protected":false},"author":1,"featured_media":16622,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[99,3,17],"tags":[2288,18,2287],"class_list":["post-16617","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-division-07-thermal-and-moisture-protection","category-all-posts","category-division-14-elevating-devices","tag-crystalling","tag-elevators","tag-waterproofing","generate-columns","tablet-grid-50","mobile-grid-100","grid-parent","grid-33"],"_links":{"self":[{"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/posts\/16617","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/comments?post=16617"}],"version-history":[{"count":2,"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/posts\/16617\/revisions"}],"predecessor-version":[{"id":20452,"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/posts\/16617\/revisions\/20452"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/media\/16622"}],"wp:attachment":[{"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/media?parent=16617"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/categories?post=16617"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/essential.construction\/academy\/wp-json\/wp\/v2\/tags?post=16617"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}